1. Field of the Invention
The present invention relates to an information communications apparatus for a vehicle which is used for communicating a wide variety of information (e.g., information on traffic and weather conditions) in various situations such as vehicle to vehicle, electronic beacon to vehicle, and information center to vehicle.
2. Description of the Prior Art
As an example of an information communications apparatus for a vehicle, Japanese Laid-Open Patent Publication No. HEI 9-259387 discloses a traffic congestion information detector, a traffic congestion information system and a traffic congestion information receiving/displaying apparatus.
The purpose of the arrangement disclosed in this publication is to make it possible to detect traffic congestion information without having to provide any facilities on the road. In this connection, FIG. 15 shows the outline of such arrangement, in which a vehicle 1 is provided with a traffic congestion information detector 2 and a traffic congestion information receiving/displaying device 3.
The traffic congestion information detector 2 uses GPS navigation or the like to continuously detect the current position of the vehicle. Further, every time the vehicle moves through a predetermined traveling interval the traffic congestion information detector 2 automatically calculates the time required to pass through such traveling interval. The information of the required time is transmitted to a traffic information center 4 via radio communication together with the information of the identification number of such traveling interval.
At the traffic information center 4, the traveling interval identification number and the required time thereof transmitted via radio from each vehicle 1 are received and stored. Then, the traffic center 4 transmits the newest required time for each traveling interval by radio to the surrounding vehicles 1. This information transmitted by the traffic information center 4 is received from the traffic congestion information receiving/displaying device 3 mounted in each vehicle 1. Then, the driver or someone else in the vehicle 1 can selectively display the required time for an traveling interval.
However, in such prior art technology described above when many vehicles transmit information from points close to each other using the same transmission frequency, simultaneous transmission by the vehicles can cause radio interference, whereby it becomes impossible for the traffic information center to properly receive the transmitted information.
Further, if different communications channels (communications line) are assigned (allotted) to respective vehicles in an attempt to overcome such problem, a considerable burden will be placed on the communication equipment of the traffic information center 4.
Furthermore, in the prior art technology described above, communication is carried out between vehicles and a traffic information center, but depending on a content of the information to be transmitted, there are cases where it is more convenient to carry out direct vehicle-to-vehicle communication. However, in such a case, a communications apparatus to be mounted in a vehicle must have a function that enables to communicate with each of many communications apparatuses mounted in vehicles, but this results in increased cost due to such function.
In view of the above-mentioned problem, a main object of the present invention is to provide an information communications apparatus for a vehicle which is capable of transmitting and receiving information without interference even when there are a plurality of vehicles which transmit information from points close to each other.
Another object of the present invention is to provide an information communications apparatus for a vehicle which is capable of transmitting and receiving information without increasing the burden in communications equipment.
In order to achieve these objects, the present invention is directed to an information communications apparatus for a vehicle, which comprises:
position measuring means for measuring position of the vehicle;
transmission channel setting means for setting an information transmission channel by utilizing the positional information of the vehicle which is measured by the position measuring means; and
information transmission means for transmitting information externally by means of the transmission channel set by the transmission channel setting means.
In this invention, it is preferred that when the vehicle reaches at a set specified point or area or at a point which is far from the specified position or area by a predetermined distance, the transmission channel setting means sets a channel to a transmission channel which is previously assigned to the specified point or area, and then the information transmission means transmits the information by means of the established transmission channel.
As described above, in the present invention individual transmission channels are previously assigned to the respective specified points or areas, and the transmission is carried out using the assigned transmission channel. This makes it possible to receive information without interference as long as transmission channels are different to each other, even in the case where a plurality of vehicles transmit information from points close to each other.
Further, it is also preferred that the communications apparatus further comprises memory means which stores a table having a collection of data of each specified point with respect to its assigned transmission channel or having a collection of data of each specified area with respect to its assigned transmission channel, wherein the transmission channel setting means establishes the transmission channel assigned to the specified point or area corresponding to the vehicle position which is measured by the position measuring means by referring to the table In the memory means.
Preferably, in the present invention, different transmission channels are assigned to the adjacent specified points or areas.
Alternatively, it is also preferred that different transmission channels are assigned to each of roads or each of traffic lanes, wherein the channel setting means establishes the transmission channel which is previously assigned to a road or lane along which the vehicle is travelling when the vehicle reaches at the intersection or at a position which is far from the intersection by a predetermined distance, and then the information transmission means transmits the information by means of the established transmission channel.
In this case, it is preferred that the information communications apparatus further comprises memory means which stores a table having a collection of data of each road or lane with respect to its assigned transmission channel, wherein the transmission channel setting means establishes the transmission channel assigned to the road or lane in association with the vehicle position measured by the position measuring means by referring to the table stored in the memory.
Preferably, in the present invention, different transmission channels are assigned to the adjacent specified points or areas.
The information communications apparatus further comprises reception channel setting means for setting a reception channel for receiving information; and information reception means for receiving Information transmitted from other vehicle or an information center using the established reception channel set by the reception channel setting means.
In this case, it is preferred that the reception channel setting means is constructed such that an operator in the vehicle can select a desired reception channel.
In a preferred form, when the vehicle reaches at the specified intersection or at a position far away from the intersection by a predetermined distance, the reception channel setting means switches the reception channel in a sequential manner to each of the transmission channels assigned to each of the roads or lanes connected to the intersection by referring to the table stored in the memory means
The present invention is also directed to an information communications system between at least two vehicles, in which each of the vehicles comprises:
position measuring means for measuring position of the vehicle;
transmission channel setting means for setting an information transmission channel by utilizing the positional information of the vehicle which is measured by the position measuring means;
information transmission means for transmitting information externally by means of the transmission channel set by the transmission channel setting means:
reception channel setting means for setting a reception channel for receiving information; and
information reception means for receiving information transmitted from other vehicle or an information center using the established reception channel set by the reception channel setting means,
wherein the transmission vehicle transmits the information by means of the established transmission channel set by the transmission setting means and the reception vehicle receives the transmitted information by means of the reception channel established by the reception channel setting means.
In this case, it is preferred that when the vehicle reaches at a previously set specified point or area or at a point which is far from the specified point or area by a predetermined distance, the transmission channel setting means sets a channel to a transmission channel which is assigned to the specified point or area, and then the information transmission means transmits the information by means of the established transmission channel.
Further, it is also preferred that each vehicle further comprises memory means which stores a table having a collection of data of each specified point with respect to its assigned transmission channel or having a collection of data of each specified area with respect to its assigned transmission channel, wherein the transmission channel setting means establishes the transmission channel assigned to the specified position or area corresponding to the vehicle position which is measured by the position measuring means by referring to the table in the memory means.
In this case, it is preferred different transmission channels are assigned to the adjacent specified positions or specified areas.
Further, it is also preferred that the information communications system further comprises means for determining as to whether there is any other vehicle which is transmitting information by means of the same transmission channel.
Other aspect of the present invention is directed to an information communications system for communication between at least one vehicle and an information center, in which each vehicle comprises:
the position measuring means for measuring position of the vehicle;
transmission channel setting means for setting an information transmission channel by utilizing the positional Information of the vehicle which is measured by the position measuring means; and
information transmission means for transmitting information externally by means of the transmission channel set by the transmission channel setting means,
wherein the vehicle transmits the information to the information center by means of the established transmission channel set by the transmission setting means.
In this case, it is preferred that when the transmission vehicle reaches at a specified point or area or a point which is far from the specified point or area by a predetermined distance, the transmission channel setting means set a channel to a transmission channel which is previously assigned to the specified position or area, and then the information transmission means transmits the information by means of the established transmission channel.
Further, it is also preferred that each vehicle further comprises memory means which stores a table having a collection of data of each specified position with respect to its assigned transmission channel or having a collection of data of each specified area with respect to its assigned transmission channel, wherein the transmission channel setting means establishes the transmission channel assigned to the specified position or area corresponding to the vehicle position which is measured by the position measuring means by referring to the table in the memory means.
In this case, it is preferred that different transmission channels are assigned to the adjacent specified positions or specified areas.
Further, it is also preferred that the information communications system further comprises means for determining as to whether there is any other vehicle which is transmitting information by means of the same transmission channel.